You know, despite being a standard file format, PowerPoint presentations are surprisingly incompatible across different computers, even when those computers are running the same version of Office. I get that it's difficult to create a file format that can be reliably reproduced on any screen resolution, with any file system arrangement and with any level of computer power, but it still surprises me that the same PowerPoint file, on two very similar computers, will work just fine on one and struggle on the other. Judging by how many versions of Office Microsoft has gone through without getting it right, this must be a crazy-difficult problem.
Mokalus of Borg
PS - Though I haven't done much testing with Office 2013.
PPS - Maybe it's gotten a bit better.